> ## Documentation Index
> Fetch the complete documentation index at: https://staging.docs.aile.tech/llms.txt
> Use this file to discover all available pages before exploring further.

# Rates & fees

> Live midmarket rate and spread per pair, what you pay, and where each coin's midmarket rate comes from.



\<table><thead><tr><th>Pair</th>
              
                  \<th>Midmarket
USD per coin</th>
                  \<th>Spread, bps
buy / sell</th></tr></thead>
          \<tbody /></table>

**Midmarket** is the mid rate the maker prices from, in USD per coin; **Spread** is the distance of the firm
quote's price from it, in basis points, for buying the coin with USDC and for selling it. Sizes are on
[Trade sizes and limits](https://staging.docs.aile.tech/reference/trade-sizes.md).## What you pay| Cost | Who takes it | How much |
| - | - | - |
| Spread | The market maker that signed the quote | Inside the rate. `buyAmount / sellAmount` is the all-in price; its distance from `referenceRate` is the spread in the table above. |
| Protocol fee | Aile | **None today.** `fees.bps` and `fees.amount` in every quote read `0`; `fees.recipient` is the zero address. |
| Gas | You, on Base | A fill uses about 240k gas: about a cent on Base. |There is no subscription, no minimum volume and no charge for quotes you do not fill.Because a quote is a signed order, the rate you see is the rate you get: no re-pricing between the quote and
the fill, no slippage tolerance to set. The quote carries `referenceRate` (the midmarket rate it was priced
from) and `sellAmount`/`buyAmount` (the exact amounts), so the spread of every quote can be checked.## Midmarket ratesThe midmarket rate is the one the maker actually prices from. Today every pair is priced from a public
Chainlink feed on Base, read on chain at the moment of the quote. `reference.source` on each level says
which kind of source the rate came from: `chainlink` for a feed, `api` for a rate read from live order books.### EURC| | |
| - | - |
| Midmarket rate | Chainlink **EURC/USD** feed on Base, [`0x9867…01e0`](https://basescan.org/address/0x9867186e52d2F1C2c565CDA6E747101Fa56501e0) |
| Updates | A new round when the rate moves 0.1 % or after 1 hour |### XSGD| | |
| - | - |
| Midmarket rate | Chainlink **SGD/USD** feed on Base, [`0x8157…949b`](https://basescan.org/address/0x81575495532fB311Efc5C993B612564274F0949b) |
| Updates | A new round when the rate moves 0.5 % or after 24 hours: in practice about one print a day |### IDRX| | |
| - | - |
| Midmarket rate | Chainlink **IDR/USD** feed on Base, [`0x05A6…ef97`](https://basescan.org/address/0x05A6cF213EcC5501A11a08EBefA4A8a60313ef97) |
| Updates | A new round when the rate moves 0.3 % or after 1 hour |## Reading it from the API```bash theme={null}
curl -s https://app.aile.tech/api/base/v1/levels | jq '.levels[] | {sellToken, buyToken, reference, maxFirmSize}'
````reference.rate` is the midmarket rate, `reference.source` its kind (`chainlink` or `api`), `reference.at` its
time. No key is needed; the machine-readable form is documented at [`GET /v1/levels`](https://staging.docs.aile.tech/api-reference/get-levels).


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